Identification of cytotoxic T lymphocyte (CTL) epitope in Iran S bovine ephemeral fever virus (BEFV) glycoprotein G for vaccine development

During industrial-scale production of viruses for vaccine manufacturing, anti-viral response of host cells can dampen maximal viral antigen yield. In addition to interferon responses, many other cellular responses, such as the AMPK signaling pathway or senescence-like response may inhibit or slow down virus amplification in the cell culture system. In this study, we first performed a Gene Set Enrichment Analysis of the whole-genome mRNA transcriptome and found a senescence-like cellular response in BHK-21 cells when infected with bovine ephemeral fever virus (BEFV). To demonstrate that this senescence-like state may reduce virus growth, BHK-21 subclones showing varying degrees of a senescence-like state were infected with BEFV. The results showed that the BHK-21 subclones showing high senescence staining could inhibit BEFV replication while low senescence-staining subclones are permissive to virus replication. Using a different approach, a senescence-like state was induced in BHK-21 using a small molecule, camptothecin (CPT), and BEFV susceptibility were examined. The results showed that CPT-treated BHK-21 is more resistant to virus infection. Overall, these results indicate that a senescence-like response may be at play in BHK-21 upon virus infection. Furthermore, cell clone selection and modulating treatments using small molecules may be tools in countering anti-viral responses.

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Isolation and genetic characterization of bovine ephemeral fever virus from epidemic-2020 in Turkey

Tropical Animal Health and Production ◽

10.1007/s11250-021-02715-1 ◽

2021 ◽

Vol 53 (2) ◽

Author(s):

Ilke Karayel-Hacioglu ◽

Selda Duran Yelken ◽

Yaser Vezir ◽

Nilay Unal ◽

Feray Alkan

Keyword(s):

Genetic Characterization ◽

Fever Virus ◽

Bovine Ephemeral Fever Virus ◽

Bovine Ephemeral Fever

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Inhibitors of phosphatidylinositol 3-kinase and mTOR but not Akt enhance replication of bovine ephemeral fever virus

The Veterinary Journal ◽

10.1016/j.tvjl.2009.11.003 ◽

2011 ◽

Vol 187 (1) ◽

pp. 119-123 ◽

Cited By ~ 7

Author(s):

Wen T. Ji ◽

Ying C. Wang ◽

Feng L. Lin ◽

Ming H. Liao ◽

Wen L. Shih ◽

...

Keyword(s):

Fever Virus ◽

Phosphatidylinositol 3 Kinase ◽

Bovine Ephemeral Fever Virus ◽

Bovine Ephemeral Fever ◽

Phosphatidylinositol 3

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Role of a Cytotoxic-T-Lymphocyte Epitope-Defined, Alternative gag Open Reading Frame in the Pathogenesis of a Murine Retrovirus-Induced Immunodeficiency Syndrome

Journal of Virology ◽

10.1128/jvi.79.7.4308-4315.2005 ◽

2005 ◽

Vol 79 (7) ◽

pp. 4308-4315 ◽

Cited By ~ 8

Author(s):

Arti Gaur ◽

William R. Green

Keyword(s):

T Lymphocyte ◽

Cytotoxic T Lymphocyte ◽

Leukemia Virus ◽

Protein S ◽

Initiation Site ◽

Open Reading Frame ◽

Reading Frame ◽

Ctl Epitope ◽

Immunodeficiency Syndrome

ABSTRACT LP-BM5 murine leukemia virus-infected C57BL/6 mice develop profound immunodeficiency and B-cell lymphomas. The LP-BM5 complex contains a mixture of defective (BM5def) and replication-competent helper viruses among which BM5def is the primary causative agent of disease. The BM5def primary open reading frame (ORF1) encodes the single gag precursor protein (Pr60 gag ). Our lab has recently demonstrated that a novel immunodominant cytotoxic-T-lymphocyte (CTL) epitope (SYNTGRFPPL) is expressed from a +1-nucleotide translational open reading frame of BM5def during the course of normal retrovirus expression. The SYNTGRFPPL CTL epitope may be generated from either of two initiation methionines present, ORF2a or ORF2b, located downstream of the ORF1 initiation site. This study investigates the role(s) of the alternative ORF2-derived gag protein(s) of BM5def in viral pathogenesis. We have examined the disease-inducing capabilities of mutant viruses in which the translational potential of either the initiating ORF2a or ORF2b AUG has been disrupted. Although these mutated viruses are capable of wild-type ORF1 expression, they are unable to induce disease. Our data strongly suggest the existence of a novel ORF2 product(s) that is required for LP-BM5-induced pathogenesis and have potentially broad implications for other retroviral diseases.

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Efficient Generation of a Hepatitis B Virus Cytotoxic T Lymphocyte Epitope Requires the Structural Features of Immunoproteasomes

Journal of Experimental Medicine ◽

10.1084/jem.191.3.503 ◽

2000 ◽

Vol 191 (3) ◽

pp. 503-514 ◽

Cited By ~ 108

Author(s):

Alice J.A.M. Sijts ◽

Thomas Ruppert ◽

Barbara Rehermann ◽

Marion Schmidt ◽

Ulrich Koszinowski ◽

...

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

T Lymphocyte ◽

Cytotoxic T Lymphocyte ◽

Structural Features ◽

Core Antigen ◽

Ctl Epitope ◽

Cleavage Specificity ◽

B Virus ◽

Ifn Γ

Interferon (IFN)-γ–induced cells express the proteasome subunits low molecular weight protein (LMP)2, LMP7, and MECL-1 (multicatalytic endopeptidase complex–like 1), leading to the formation of immunoproteasomes. Although these subunits are thought to optimize MHC class I antigen processing, the extent of their role and the mechanistic aspects involved remain unclear. Herein, we study the proteolytic generation of an human histocompatibility leukocyte antigen (HLA)-Aw68–restricted hepatitis B virus core antigen (HBcAg) cytotoxic T lymphocyte (CTL) epitope that is recognized by peripheral blood lymphocytes from patients with acute self-limited but not chronic hepatitis B virus (HBV). Immunological data suggest that IFN-γ–induced rather than uninduced HeLa cells process and present the HBV CTL epitope upon infection with HBcAg-expressing vaccinia viruses. Analyses of 20S proteasome digests of synthetic polypeptides covering the antigenic HBcAg peptide demonstrate that only immunoproteasomes efficiently perform the cleavages needed for the liberation of this HBV CTL epitope. Although the concerted presence of the three immunosubunits appears essential, we find that both catalytically active LMP7 and inactive LMP7 T1A support CTL epitope generation. We conclude that LMP7 influences the structural features of 20S proteasomes, thereby enhancing the activity of the LMP2 and MECL-1 catalytic sites, which provide cleavage specificity. Thus, LMP7 incorporation is of greater functional importance for the generation of an HBV CTL epitope than cleavage specificity.

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Potential of recombinant Mycobacterium paragordonae expressing HIV-1 Gag as a prime vaccine for HIV-1 infection

Scientific Reports ◽

10.1038/s41598-019-51875-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Byoung-Jun Kim ◽

Bo-Ram Kim ◽

Yoon-Hoh Kook ◽

Bum-Joon Kim

Keyword(s):

Immune Responses ◽

T Lymphocyte ◽

Antibody Production ◽

Vaccine Development ◽

Cytotoxic T Lymphocyte ◽

Mycobacterial Infection ◽

Temperature Sensitive ◽

T Lymphocyte Proliferation ◽

Antigen Presenting ◽

Hiv 1

Abstract Recombinant Mycobacterium strains such as recombinant BCG (rBCG) have received considerable attention for the HIV-1 vaccine development. Recently, we described a temperature-sensitive Mycobacterium paragordonae (Mpg) strain as a novel live tuberculosis vaccine that is safer and showed an enhanced protective effect against mycobacterial infection compared to BCG. We studied the possibility of developing a vaccine against HIV-1 infection using rMpg strain expressing the p24 antigen (rMpg-p24). We observed that rMpg-p24 can induce an increased p24 expression in infected antigen presenting cells (APCs) compared to rBCG-p24. We also observed that rMpg-p24 can induce enhanced p24 specific immune responses in vaccinated mice as evidenced by increased p24-specific T lymphocyte proliferation, gamma interferon induction, antibody production and cytotoxic T lymphocyte (CTL) responses. Furthermore, an rMpg-p24 prime and plasmid DNA boost showed an increased CTL response and antibody production compared to rBCG or rMpg alone. In summary, our study indicates that a live rMpg-p24 strain induced enhanced immune responses against HIV-1 Gag in vaccinated mice. Thus, rMpg-p24 may have potential as a preventive prime vaccine in a heterologous prime-boost regimen for HIV-1 infection.

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